During the manufacture of semiconductor devices, components are typically transported through various processing points in carrying devices. For example, during the manufacture of 300 mm wafers, the wafers may be transported through the manufacturing line in a Front Opening Unified Pod (FOUP). Conventional FOUPs typically comprise a box-like structure that can carry a number of wafers (for example, twenty five) inside the box-like structure. The FOUP generally comprises a removable door for allowing access to the interior of the box-like structure and any wafers accommodated therein. The FOUP also typically includes locating features (for example, recesses in a bottom surface of the box-like structure) that are structured and arranged to engage with coupling pins located at the various processing points where the FOUP is to be opened for access to the wafers therein.
It is well understood that foreign material (for example, dirt and other contaminants) interferes with microscopic semiconductor devices. Accordingly, great effort is taken to reduce the amount of foreign material that interferes with the microscopic devices that are being built on the wafers carried in FOUPs. However, repeated opening and closing of a FOUP disadvantageously allows foreign material to collect on the microscopic devices on the wafers, thereby reducing wafer yield.
One method of combating the presence of foreign material is to routinely unload and clean the FOUPs. For example, at predetermined time intervals, each FOUP may be unloaded of any wafers and subjected to a cleaning that involves the use of jets of hot, de-ionized water, exposure to radiation, spin drying, etc. In this manner, foreign material that may have accumulated on the walls of the FOUP may be removed so that it does not become re-deposited on wafers inside the FOUP. However, routine cleaning only partly addresses the problem of contamination, and any foreign material that accumulates on the walls of a FOUP in between cleanings is free to re-deposited on wafers inside the FOUP.
Accordingly, there exists a need in the art to overcome the deficiencies and limitations described hereinabove.